1. Field of the Invention
The present invention relates to oil well monitoring equipment, and particularly to a system for measuring multi-phase fluid flow characteristics (such as fluid density, water cut, flow rate, etc.) in a multi-phase fluid, such as crude oil containing a mixture of oil and water, in pipes either down hole or at the surface of the well.
2. Description of the Related Art
When dealing with crude oil, either from an oil well or when the oil is still “down-hole” (i.e., still in an underground reservoir or the like), it is very important to be able to monitor and measure various fluid properties of the crude oil. This is relatively difficult at the crude oil stage, since crude oil is typically in the form of a multi-phase fluid, consisting of at least both oil and water. The multi-phase nature of the fluid makes accurate on-site monitoring of fluid mixture density, water content (or “water cut”) and flow rate very difficult due to the fluid dynamics and complex makeup of the crude oil mixture.
Due to the inherent difficulties in making direct measurements from such a two-phase mixture, the oil and water are typically separated from one another before measurements are made. This, however, requires an interruption of the continuous industrial process of crude oil extraction. Additionally, a wide variety of devices must be used in such separation-based measurement, including, for example, both phase fraction and phase velocity measurement devices simply to measure the water content in the multi-phase fluid. It would obviously be desirable to be able to directly measure fluid properties of the multi-phase fluid with a single set of instruments and without having to first separate the oil from the water.
Thus, a system for measuring multi-phase fluid flow characteristics solving the aforementioned problems is desired.